14
4.5
Configuration parameters
When
PAR
is on the display you may enter the configura-
tion menu by pressing the
?
key. In this menu the most
important configuration and signal modification parame-
ters are viewable. You may view the current value and edit
them by pressing the
?
key at the relevant parameter.
The name of the parameter will appear on the upper row
of the display and the current value is on the lower row.
4.5.1 Performance level,
PERF
If you want to change the tuning of the valve position
control, the
PERF
selection is available. The default fac-
tory value is
C
.
❑
Once
PERF
is displayed press the
?
key to
enter the edit state and
PERF
starts to blink.
❑
Select between five values by pressing the
+
or
-
key.
❑
After the desired value is displayed, press the
key
?
to conclude the operation
4.5.2 Low cut-off,
CUTL
Low cut-off safety range
CUTL
ensures the valve closing
against mechanical travel stops. The factory default
value is 2 %.
❑
Once
CUTL
is displayed press the
?
key to
enter the edit state and the
CUTL
will start to
blink. The currently selected value appears as a
percentage (
%
) on the display
❑
Modify the parameter value by pressing
+
or
-
keys alternately until the desired value appears
on the display.
❑
After the desired value is displayed, press the
key
?
to conclude the operation.
4.5.3 Signal direction,
DIR
The opening and closing direction of the valve with rais-
ing current loop signal is defined by signal direction
parameter
DIR
.
❑
When
DIR
is displayed press the
?
key to enter
the edit state and
DIR
starts to blink.
❑
Select either the
OPE
or
CLO
values by pressing
the
+
and
-
keys. The value
OPE
signifies the
raising signal 4–20 mA to open the valve and
CLO
means the raising signal to close the valve.
❑
To conclude, press the
?
key when the desired
value is shown on the display.
See default values in Fig. 6.
4.5.4 Valve type,
VTYP
To compensate for nonlinearity of the position feedback
caused by the actuator linkage mechanism of a linear
control valve, the appropriate selection must be made on
the
VTYP
display.
❑
After selecting
VTYP
on the display, press the
?
key to enter the edit state and the
VTYP
starts to
blink.
❑
Select between three values
rot
,
LIn
or
nCG
using the
+
and
-
keys. The value
rot
indi-
cates a rotary valve and
LIn
a linear valve. Use
nCG
only for nelesCV Globe valves to accommo-
date special linkage geometry.
❑
To conclude press the
?
key when the desired
value is shown on the display.
4.5.5 Actuator type,
ATYP
In order to optimise the control performance the device
needs to be informed about the actuator type.
❑
After selecting
ATYP
on the display, press the
?
key to enter the edit state and
ATYP
starts to blink.
❑
Select between two values
2
-
A
or
1
-
A
using the
+
and
-
keys. The value
2
-
A
indicates a double
acting actuator and
1
-
A
a single acting actuator.
❑
To conclude press the
?
key when the desired
value is shown on the display.
4.5.6 Positioner fail action,
PFA
Set value
CLO
for double acting actuators. For single act-
ing actuators set value in the spring direction. This action
will also take place when the controller software discov-
ers a fatal device failure. See Fig. 6 for correct settings.
❑
Once
PFA
is displayed, press the
?
key to enter
the edit state and the
PFA
will start blinking.
❑
You may select between two values by pressing
the
+
or
-
key. The
CLO
value indicates that the
valve ought to be closed in fail action situations.
The
OPE
value indicates the valve to be opened in
fail action situations.
Fig. 13
Setpoint change in MAN mode
Table 4
Selection
Meaning
Description
A
Aggressive
Immediate response to
signal changes, overshoots
b
Fast
Fast response to signal
changes, small overshooting
C
Optimum
Very small overshoot with
minimum step response
time
d
Stable
No overshooting, slow
response to input signal
changes
E
Maximum stability
No overshooting,
deadband may increase,
slow but stable behaviour
For use with volume boosters and/or very fast actuators,
additional performance levels A1 to D1 can be used.
Characteristics of these extended levels are the same as
those in the table above. However, with performance level
settings A1 to D1, adaptive properties of the ND9000
control algorithm are disabled.
Содержание ND9200H
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